Various types of handling trays for semiconductor substrates are used in the industry. One type consists of an essentially rectangular--in cross section--quartz glass tube which has slits cut into the sides extending towards the interior of the tube as well as slits cut in alignment in the bottom wall thereof. This type of holder has been used in the industry under part No. Q-B 3/112 3 C 7411 Ku by Heraeus Quarzschmelze, and known as "Quartz Glass for Semiconductor Technology" and described in a prospectus therefor. The end regions of the quartz glass tube are formed with coaxial bores extending from the top to the bottom which are used to shift the tubular carriers into the diffusion tubes for treatment of the semiconductor substrate after the substrates have been loaded thereon. The substrates are supported at three points symmetrically within the holder. This symmetrical three-point support has been found eminently suitable. The manufacture of the holders for the substrates, however, is relatively expensive.